The present invention is directed generally to a manually programmable multi-channel communication network capable of linking a plurality of different information terminal locations within an office building or the like. More particularly, the invention relates to a mechanically programmable interconnection or "cross-connect" system for a telephone installation providing service to a multiple telephone service area. The invention is most advantageously employed in an intrabuilding environment where a large number of individual telephone instruments or handsets are located throughout a given service area.
In recent years, the telephone industry has made great strides in reducing the costs of telephone equipment and the expenses attendant to its installation and maintenance. An area of particular concern has been the need to reduce the labor costs in initially arranging or "programming" and thereafter rearranging or "reprogramming" the numerous telephone numbers to different locations within a given service area. Accordingly, modularized systems have been developed which reduce field wiring and simplify the procedures employed in installing or reprogramming the telephone system. One example of a prior art system intended to address these problems is that disclosed in U.S. Pat. No. 3,869,582 owned by Allstate Insurance Company. The telephone system described in the Allstate patent generally includes a central distribution panel and one or more remote or "satellite" distribution panels which are permanently wired to the central distribution panel. Patchcords are used with both the central and satellite panels to enable physical rearrangement or relocation of the telephone numbers to different parts of the service area. The Allstate system, however, is still relatively expensive, requiring multiple distribution panels, and often requires rearrangement of patchcords at more than one location, which complicates the reprogramming procedure and increases the attendant reconnection costs, as well.
Another prior art system is disclosed in U.S. patent application Ser. No. 058,885 filed on July 19, 1979 in the name of Arie Verhagen and assigned to Bunker Ramo Corporation, the assignee of this application. The Verhagen application discloses an interconnection or cross-connect approach wherein the incoming telephone lines are hard-wired or otherwise affixed to individual receptacle members and the station cables are field terminated to individual plug connectors. The Verhagen system represents a significant advance over the Allstate approach, since it is extremely low cost, it saves space and only a single junction is required which can be serviced by relatively unskilled personnel. Nevertheless, it suffers from the disadvantage that each of the station cables must be terminated in the field to a connector which may be subjected to many mating cycles during its useful life. Such field terminable connectors are inherently less reliable than factory assembled terminations and their use increases the costs of initial installation.
Other electronic systems have been developed for electronic reprogramming of telephone systems but these require specific equipment to electronically "enter" the system as well as a trained operator skilled in working with computer software.